Platform review round 2: audit logging migration, nav unification, DB indexes, and UI polish

- Migrate ~41 inline audit log calls to shared logAudit() utility across all routers
- Add transaction-aware prisma parameter to logAudit() for atomic operations
- Unify jury/mentor/observer navigation into shared RoleNav component
- Add composite DB indexes (Evaluation, GracePeriod, AuditLog) for query performance
- Fix profile page: consolidate dual save buttons, proper useEffect initialization
- Enhance auth error page with MOPC branding and navigation
- Improve observer dashboard with prominent read-only badge
- Fix DI-3: fetch projects before bulk status update for accurate notifications
- Remove unused aiBoost field from smart-assignment scoring
- Add shared image-upload utility and structured logger module

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/server/services/smart-assignment.ts

@@ -24,7 +24,6 @@ export interface ScoreBreakdown {
   bioMatch: number
   workloadBalance: number
   countryMatch: number
-  aiBoost: number
 }
 
 export interface AssignmentScore {
@@ -367,7 +366,6 @@ export async function getSmartSuggestions(options: {
           bioMatch: bioScore,
           workloadBalance: workloadScore,
           countryMatch: countryScore,
-          aiBoost: 0,
         },
         reasoning,
         matchingTags,
@@ -490,7 +488,6 @@ export async function getMentorSuggestionsForProject(
         bioMatch: bioScore,
         workloadBalance: workloadScore,
         countryMatch: countryScore,
-        aiBoost: 0,
       },
       reasoning,
       matchingTags,